1. Field of Use
The present invention relates to data processing systems. More specifically, it relates to adapters for allowing communications between a peripheral controller and a peripheral device.
2. Prior Art
In recent years, peripheral controllers have been used to simultaneously control communication to and from a plurality of peripherals. Each of the controlled peripherals may have operating characteristics that differ greatly from its fellow peripherals. Instead of placing the burden on the controller to keep track of all the different operating characteristics, one solution has been to provide the controller with a standard protocol and to provide each peripheral device with an adapter which converts each peripheral device's communications into the standard protocol. Such adapters have also been used to resolve the need for the varying buffering requirements of different types of peripherals. A typical example of an adapter being used with a standardized controller is shown in pending U.S. patent application Ser. No. 057,553, filed June 3, 1987 by Lewis et al, now abandoned.
Especially troublesome has been the problem of how to design an adapter that is connected to an intelligent device, for the protocol tends to be more sophisticated with intelligent devices than with nonintelligent devices. One solution has been to include a microprocessor in the adapter that controls data transfers. However, these microprocessors increase adapter cost and size.